Introduction to Immunology

Study Notes

Learning objectives: explain the components of the immune system, including lymphoid organs, cells, and soluble mediators.

Immunology is important for pharmacists to learn because it involves drugs that induce specific immune responses, regulate immunologic functions, and use antibodies and cytokines for therapeutics and diagnosis.

Immune system consists of immune organs/tissues, immune cells, and immune molecules.
Lymphoid organs: primary (bone marrow, thymus) and secondary (spleen, lymph nodes, tonsils, appendix, Peyer's patches).
Lymphatic system drains excess interstitial fluid, transports dietary lipids, and carries out immune response.

Peripheral blood mononuclear cells (PBMCs) include lymphocytes and monocytes.
Neutrophils: first responder to microbial infection, die after phagocytosing pathogens, forming majority of pus.
Eosinophils: involved in allergic reactions and parasitic infections, release chemical products that perforate cell membranes.
Basophils: involved in inflammatory response, release histamine, functionally similar to mast cells.
Monocytes: largest type of leukocyte, share phagocytosis duties with neutrophils, mature into macrophages.
Lymphocytes (B and T cells): responsible for antibody production, antigen presentation, and elimination of viral infections.

Antibodies (Ab): Y-shaped proteins produced by B cells in response to antigen, 5 isotypes (IgG, IgM, IgA, IgD, and IgE).
Complement: a system of proteins that help eliminate pathogens.
Cytokines: immunoregulatory proteins secreted by cells, including interleukin, lymphokine, monokine, interferon, and chemokine.
Cytokines function: induction and regulation of cellular interactions involving immune, inflammatory, and hematopoietic systems.

Innate immunity: immediate, non-specific response to infection.
Adaptive immunity: delayed, specific response to infection, involves immunological recognition.